It is known to provide in a conventional bath a free standing seat structure provided with pneumatically operated means which can move the seat between a vertically raised position, in which the seat is located at the upper edge of the sides of the bath, and a lowered position in which the seat is located near to the bottom of the bath. The disadvantages of such a seat structure are that the seat is free standing and may inadvertently be moved along the bath accidentally. The flexible conduits for conveying the compressed air to the seat extend into the bath and can become bent or deformed so as to cut off the supply of compressed air to the seat. The seat cannot be pivoted so as to lie transversely of the bath and therefore a disabled person may experience difficulty in being able to move onto and off the seat.